Beneficial and perverse effects of isoniazid preventive therapy for latent tuberculosis infection in HIV–tuberculosis coinfected populations

Abstract

In sub-Saharan Africa, where the emergence of HIV has caused dramatic increases in tuberculosis (TB) case notifications, new strategies for TB control are necessary. Isoniazid preventive therapy (IPT) for HIV–TB coinfected individuals reduces the reactivation of latent Mycobacterium tuberculosis infections and is being evaluated as a potential community-wide strategy for improving TB control. We developed a mathematical model of TB/HIV coepidemics to examine the impact of community-wide implementation of IPT for TB–HIV coinfected individuals on the dynamics of drug-sensitive and -resistant TB epidemics. We found that community-wide IPT will reduce the incidence of TB in the short-term but may also speed the emergence of drug-resistant TB. We conclude that community-wide IPT in areas of emerging HIV and drug-resistant TB should be coupled with diagnostic and treatment policies designed to identify and effectively treat the increasing proportion of patients with drug-resistant TB.